Bird an inch short? It’ll blow away (5)
I believe the answer is:
chaff
'it'll blow away' is the definition.
(corn husk likely to blow away in the wind)
I don't understand the remainder of the clue.
(Other definitions for chaff that I've seen before include "Light-hearted banter" , "Corn-husks separated from the grain" , "Refuse from threshing" , "Tease in good-humoured way" , "something worth little" .)